Passage
Brown and his men, huddling round a fire. ate the last of the food that Kassim had brought them that day. Comelius sat among them, half-asleep. Then one of the crew remembered that some tobacco had been left in the boat, and said he would go and fetch it. He didn't think there was any danger in going to the creek in the dark. He disappeared down the hillside, and a moment later he was heard climbing into the boat and then climbing out again.
One of them disappeared down the hill implies that

Options

A. the slope of the hill was slippery
B. he fell from the edge of the hill
C. there was suddenly a sea beside the hill
D. he walked down the hill